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    <title>recur</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>recur</b> -  a bilinear recurrent equation</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
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      <dd>
        <tt>[y]=recur(x0,var,k,n)  </tt>
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      <dd>
        <tt>[integr]=logr(k,var)  </tt>
      </dd>
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    <h3>
      <font color="blue">Description</font>
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    <p>
    computes solutions of a bilinear recurrent equation</p>
    <pre>

x(i+1)=-x(i)*(k + sqrt(var)*br(i))
   
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    <p>
    with initial value <tt>
        <b>x0</b>
      </tt> and driven by a white noise 
    of variance <tt>
        <b>var</b>
      </tt>.</p>
    <p>
    Trajectories are drawn and the empirical Lyapunov exponent 
    is returned 
    ( <tt>
        <b>x(i)</b>
      </tt> is not to much different from <tt>
        <b>exp(y*i)</b>
      </tt> )</p>
    <p>
    A theoretical computation of the Lyapunov exponent 
    is given by</p>
    <pre>

[integr]=logr(k,var)
   
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